Layered Panes

1
Layered Panes

• Manages the painting of components to simulate
  different depths. The highest depth level number
  is on top. Components at the same depth level
  are arranged top to bottom (last one added at the
  bottom).
• If you add only to the ContentPane you have a
  single layer (managed by a layout manager). The
  user adds a LayeredPane to a ConentPane to
  provided 3D. Adding a layout manager to a
  LayeredPane asks that ALL of the components be
  ordered as if they had been added to the content
  pane from highest depth and top to bottom at each
  depth.
• Constructor has no arguments. Add() has two or
  three arguments, the first being the component
  and the second being the Integer containing the
  layer depth. setLayer() can change the depth
  dynamically, and its three arguments are
  component, int layer depth, and also the position
  in the layer (0top, -1bottom, and 1 is above 2
  is above 3 )
• When there is no layout manager, you have to size
  and position each component component.setBounds(x
  ,y,width,height)
• Component.setLocation(x,y) (Note that the
  component knows its location, hence a layout
  manager sets a new value for each components
  location and bounds)

2
Root Panes

• Provided in top level containers and internal
  frames.
• Always contains a Layered Pane, a Content Pane
  and a Glass Pane. The Layered Pane is not the
  one added to the Content Pane for 3D. It holds
  the Content Pane and the Menu, both on the lowest
  level (-3000)
• The components added to the content pane are
  placed in the default layer (0).
• The palette layer (100) holds floating tool bars
  or components that cover content.
• The modal layer (200) displays internal frame
  dialogs
• The popup layer (300) display above everything
  else.
• The drag layer (400) is where moving components
  are painted to simulate their motion, and when
  dropped, they retrun to their original layer (0).
  
• When dragging, the mouse does not trigger other
  components.

3
The Glass Pane

• You can place components or graphics on the glass
  pane that will be active ONLY when the glass pane
  is visible. When visible, the glass pane
  OBSTRUCTS interaction with any component below
  it, even though that component may be visible.
• The trick is to be able to turn the glass pane on
  and off. This is done by placing the on-off
  switch on the content pane, but when it is
  OBSTRUCTED, determine if the mouse is over it and
  pass the click through (to turn off the glass
  pane.
• We need to walk through the example code with a
  keen eye as to what needs to happen